A methamphetamine user. The term was coined for the sleep deprivation crystal meth addicts usually undergo. Some users would stay up for two weeks at a time so came the phrase 'two weekers' which eventually became tweeker.

Its been days since that guys gotten any sleep or had something to eat.. he's gotta be a tweeker.

The Urban Dictionary T-Shirt

Any poor soul who has the bad ass luck of growing up in a small depressed desert town in CA or elsewhere who is emotionally addicted to CRYSTAL METH. They will kill and die for it, and can never be cured. They will want it every day for the rest of their lives. They start by doing lines, then smoke it, and eventually they graduate to "slamming" using needles. At this time, they never want to see anyone, unless they are tweeking. They are afraid of everything, except death. All of their friends are parolees, and they aint shit until they have been to prison at least once. They steal everything in sight, draw sexually explicit pictures, talk shit, disapear for days or even weeks, will physically assault the people they love, slash their own wrists and arms. They will lose up to 100 pounds in a few years. They will have spent all of their money and lost any job they might have once had. They are unemployable. They hate themselves. They will spent 5 to 40 hours straight beating off and sticking things up their asses. Some will steal panties from the apartment dryers and wear them. They will eventually accomplish self fellatio! Anything is possible with speed!!!

"Tell your tweeker friend to get the fuck out of my bathroom!"

"Palmdale is all about the tweekers. The Sherriffs do it too."

"I heard his mom tweeks with him every time her check comes."

"Dude, stop tweeking out on it for a while, They get the point, damn!"

The Urban Dictionary T-Shirt

A person who spends countless hours performing repetitive tasks while high on amphetamines or methamphetamines. Usually they hide during the day, away from the public because of the schizophrenic state and horrible complexion caused by days of sleep deprivation and not eating.

Look at that tweeker, his face is covered with scabs because he picked at his skin for hours without even thinking about what he was doing.

The Urban Dictionary T-Shirt

A person addicted to some type of speed whose favorite hobbies include taking things apart beyond recognition, sitting by the backdoor with a large knife, 'dieting', watching American Idol, and staying up for up to 2 weeks strait. They can some times be dangerous, but are usually a lot of fun.

Yea, that fucking tweeker was about to stab me when I walked through the door, but then she realized who I was! After I watched American Idol with her she gave me her TV to go across town and get her some more crystal. Yea, she's been looking really skinny...

The Urban Dictionary T-Shirt

Someone addicted to meth. Usually they are untrustworthy, incureable, and totally not themselves. When one does meth, a profound change occurs. The person is no longer themself, and will now steal anything from anyone to get money for meth, and is often alone due to the extreme paranoia induced by the comedown of the meth. First tweekers start by doing lines, then by smoking meth, then freebasing it, then by straight up injecting it. Once they inject speed, they are officially hopeless tweekers. Generally, when such means are taken to get high, the tweeker is now homeless, and disowned by his/her family, really underweight due to lack of food and sleep, and has a poor facial complexion also due to lack of food and sleep. Often, when tweekers are in such state of despair, they will do anything- and I mean anything- to get their meth. Oftentimes they will suck dick (no matter if it's a dude or a chick) and even get raped up the ass for meth. Sometimes they will sell stolen merchandise for meth. Sometimes they will even mug their own family for meth. They can be that desparate.

"Man, don't let the tweekers into your house. You ain't gonna have anythin left when they leave."